15854-60-1Relevant academic research and scientific papers
Formal α-Allylation of Primary Amines by a Dearomative, Palladium-Catalyzed Umpolung Allylation of N-(Aryloxy)imines
Mori-Quiroz, Luis M.,Londhe, Shrikant S.,Clift, Michael D.
, p. 14827 - 14846 (2020/12/02)
N-(Aryloxy)imines, readily accessible by condensation/tautomerization of (pseudo)benzylic primary amines and 2,6-di-tert-butyl-1,4-benzoquinone, undergo efficient allylation to afford a wide range of homoallylic primary amines following hydrolytic workup. Deprotonation of N-(aryloxy)imines generates a delocalized 2-azaallyl anion-type nucleophile that engages in dearomative C-C bond-forming reactions with allylpalladium(II) electrophiles generated from allylic tert-butyl carbonates. This reactivity umpolung enables the formal α-allylation of (pseudo)benzylic primary amines. Mechanistic studies reveal that the apparent regioselectivity of the desired bond-forming event is a convergent process that is initiated by unselective allylation of N-(aryloxy)imines to give several regioisomeric species, which subsequently rearrange via stepwise [1,3]- or concerted [3,3]-sigmatropic shifts, ultimately converging to provide the desired regioisomer of the amine products.
Structure-activity relationships of phenylpropanoids as antifeedants for the pine weevil Hylobius abietis
Bohman,Nordlander,Nordenhem,Sunnerheim,Borg-Karlson,Unelius
, p. 339 - 352 (2008/09/18)
Ethyl cinnamate has been isolated from the bark of Pinus contorta in the search for antifeedants for the pine weevil, Hylobius abietis. Based on this lead compound, a number of structurally related compounds were synthesized and tested. The usability of the Topliss scheme, a flow diagram previously used in numerous structure-activity relationship (SAR) studies, was evaluated in an attempt to find the most potent antifeedants. The scheme was initially followed stepwise; subsequently, all compounds found in the scheme were compared. In total, 51 phenylpropanoids were tested and analyzed for SARs by using arguments from the field of medicinal chemistry (rational drug design). Individual Hansch parameters based on hydrophobicity, steric, and electronic properties were examined. The effects of position and numbers of substituents on the aromatic ring, the effects of conjugation in the molecules, and the effects of the properties of the parent alcohol part of the esters were also evaluated. It proved difficult to find strong SARs derived from single physicochemical descriptors, but our study led to numerous new, potent, phenylpropanoid antifeedants for the pine weevil. Among the most potent were methyl 3-phenylpropanoates monosubstituted with chloro, fluoro, or methyl groups and the 3,4-dichlorinated methyl 3-phenylpropanoate.
Quantitative structure-activity relationships of pine weevil antifeedants, a multivariate approach
Sunnerheim, Kerstin,Nordqvist, Anneli,Nordlander, Goeran,Borg-Karlson, Anna-Karin,Unelius, C. Rickard,Bohman, Bjoern,Nordenhem, Henrik,Hellqvist, Claes,Karlen, Anders
, p. 9365 - 9372 (2008/03/17)
Antifeedant activity of mainly phenylpropanoic, cinnamic, and benzoic acids esters was tested on the pine weevil, Hylobius abietis (L.). Of 105 compounds screened for activity, 9 phenylpropanoates, 3 cinnamates, and 4 benzoates were found to be highly active antifeedants. To understand the structure-activity relationships of these compounds, a multivariate analysis study was performed. A number of molecular and substituent descriptors were calculated and correlated to results from two-choice feeding tests with H. abietis. Three local models were developed that had good internal predictive ability. External test sets showed moderate predictivity. In general, low polarity, small size, and high lipophilicity were characteristics for compounds having good antifeedant activity.
Synthesis and anticholinesterase activity of huperzine a analogues containing phenol and catechol replacements for the pyridone ring
Campiani, Giuseppe,Kozikowski, Alan P.,Wang, Shaomeng,Ming, Liu,Nacci, Vito,Saxena, Ashima,Doctor, Bhupendra P.
, p. 1413 - 1418 (2007/10/03)
Based upon modeling results obtained using the crystal structure of huperzine A in complex with acetylcholinesterase (AChE), two novel analogues of this potent AChE inhibitor were designed with phenol or catechol rings replacing the pyridone ring. From the modeling studies, the catechol analogue appeared capable of replacing one of the crystallographic waters bridging huperzine with Tyr 130 and Glu 199 of AChE. The synthesis of these materials by use of a palladium catalyzed bicycloannulation strategy is detailed together with the results of AChE inhibition assays.
1-hydroxy-4(3-cyclopentyloxy-4-methoxyphenyl)-2-pyrrolidone and anti-hypertensive use thereof
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, (2008/06/13)
STR1 Substituted cyclic hydroxamic acids of general formula (I) in which R1, R2 and R3 are independently hydrogen, halogen, lower alkyl, lower alkoxy, cycloalkoxy, aryloxy which is optionally substituted by 1 to 3 halogen,
Synthesis and Experimental Ionization Energies of Certain (E)-3-Arylpropenoic Acids and Their Methyl Esters
Peterson, John R.,Russell, Morley E.,Surjasasmita, Irawan B.
, p. 534 - 537 (2007/10/02)
Ionization energies for several methoxy-substituted (E)-3-arylpropenoic acids and methyl (E)-3-arylpropenoates were experimentally determined by mass spectroscopy.The title compounds were prepared in excellent yield by Knoevenagel condensation of an aromatic aldehyde with malonic acid and by Fischer esterification of the acid with methanol.
